1. Field of the Invention
This invention relates generally to a tone control apparatus for an electronic musical instrument for controlling conditions of tone such as a tone pitch, tone color, tone volume and a tone effect, and more particularly to a tone control apparatus of the preset type in which a plurality of groups of tone control data are previously stored in a memory so that such conditions of tone can be changed by reading a desired one of the plurality of groups of tone control data.
2. Prior Art
Conventionally, a tone control apparatus of such preset type comprises a plurality of preset switches or levers corresponding respectively to the plurality of groups of tone control data. When any one of the preset switches is operated, all the control data of the group corresponding to the operated preset switch are read from the memory so that the conditions of tone such as a tone pitch, tone color, tone volume and a tone effect are changed in accordance with the read control data. Thus, the performer can simultaneously change such conditions of tone only by operating a desired one of the preset switches, so that it is not necessary for the performer to operate, one after another, a plurality of tone control switches for controlling, for example, a tone pitch, a tone color, a tone volume and a tone effect, respectively.
With such conventional tone control apparatus, the plurality of preset switches are provided, in general, on a part of the electronic musical instrument so as to be arranged in one or more rows. Therefore, during performing a music, the performer must determine by his eye which one of the preset switches should be operated. It is however difficult for an unskilled performer to carry out such an operation during performing a music. In particular, it is very difficult even for a skilled performer to carry out such an operation during performing a phrase of the music which requires quick manipulations of keys of the keyboard.
Japanese Patent Laid-Open No. 57-85094 discloses another conventional tone control apparatus in which a plurality of groups of tone control data, each group corresponding to a measure of a music, are previously stored in the order of advance of the music. The plurality of tone control data are read out one after another in accordance with tempo signals, each representative of a boundary between two adjoining measures, to control the conditions of tone based on plural data contained in each read group of tone control data. Thus, the conditions of tone are automatically and sequentially changed in accordance with the advance of the music. The performer can also change, during performing the music, the conditions of tone without operating any tone control switches.
With this conventional tone control apparatus, however, the performer must store a suitable tone control data group for each measure of the music before performing the music. Thus, this conventional tone control apparatus requires much time and work before performing each set of music, and imposes a burden on the performer particularly in the case of a long music. Furthermore, since the control of tone conditions effected in accordance with the advance of the music is determined only by the groups of tone control data previously stored in the memory, the performer can not change the conditions of tone even if he so desires.